When we discussed this lab, we talked about the native species of fish in the area having to deal with extremely cold temperature. As a matter of fact, the temperature of water in a pond or river might drop very close to 0'. However, there is one thing that most fish cannot tolerate and that is freezing into solid ice. That is because liquid water does an unexpected thing when it changes from a liquid state to a solid state. It expands. When this happens to the water in a living cell, it does fatal damage to its internal structure. Here is what your TAB answer should look like:

Most living tissue will not survive freezing because liquid water will expand when it changes into ice. This increase in volume will do fatal damage to a cell and it will not be able to survive.


Some animals, such as the water bear or certain species of reptiles contain a substance that allows the water inside their cells to drop below 0' and still remain a liquid. This allows the water around them to freeze while protecting the cells inside their bodies. Therefore, these organisms can actually freeze into a solid piece of ice and seem to come back to life when the ice thaws.